The present invention relates to a new and improved construction of stitch forming device or unit, also referred to as a stitch former, for knitting machines or the like.
Generally speaking, the stitch forming device or unit of the present development is of the type containing a hook element and a closure element by means of which there can be closed the hook of the hook element, in order to knock-off or slough knitted stitches or float stitches by carrying out a relative displacement or sliding movement between the hook element and the closure element.
The use of such known stitch forming devices, for instance as knitting needles in the knitting art, as well as for the fabrication of knitting goods and also for the fabrication of hosiery goods, enables avoiding the drawbacks associated with conventional latch needles. Equally, it is possible to attain the required still greater working speeds. In particular, this is so because the necessary sliding movement for the hook element and the closure element is relatively short.
Stitch forming devices or units of such type, also designated as "compound needles", are continuously employed in warp knitting machines, for instance in Raschel knitting machines. They are constructed as latchless or tongueless hook or bearded needles and at the region of the hook, within the needle body, possess a displaceably or slidably mounted hook closure element.
With certain of such known needles at least the hook of the needle is formed from a tubular member. During the closing operation the slide element is introduced into the hollow space of the hook.
Although these so-called compound needles enable working with greater operating speeds than with the conventional latch needles, there is still present the complicated fabrication procedures associated with such needles and, thus, the relatively high production costs.
Apart from the already mentioned difficulties which arise during forming the hook from the needle body, there is present a further difficulty because there must be additionally provided in the needle body a hollow space for the mounting of the slide or displacement element. The end of the needle body, also the hook itself and the end of the closure element are relatively weak, tend to wear rapidly and, thus, have a short service life or longevity. Additionally, these known stitch forming devices or units possess a better functional reliability if they are supported by common bars and/or controlled, than if they are separately guided and controlled.